-module Sim ( initSimSpace, testSim, physStep ) where
+module Sim (
+ Simulation, simSpace,
+ ChunkType, ChunkData, chunkType,
+ initSimSpace, testSim, physStep, validDirects,
+ simToString, stringToSim
+) where
+import Debug.Trace
import Data.Vector ((!), (//))
import qualified Data.Vector as V
--- Simulation simSpace simW simH
-data Simulation = Simulation (V.Vector ChunkData) Int Int deriving (Show)
+data Simulation = Simulation
+ { simSpace :: V.Vector ChunkData
+ , simW :: Int
+ , simH :: Int
+ } deriving (Show)
-data ChunkType = Empty
+data ChunkType = Air
| Water
- | Wall deriving (Show)
+ | Wall deriving (Show, Enum)
-data ChunkData = ChunkData ChunkType deriving (Show)
+data ChunkData = ChunkData
+ { chunkType :: ChunkType
+ } deriving (Show)
-- vec accessors
-veccGet v w i = v ! i
-simGet (Simulation s w _) i = veccGet s w i
+simGet Simulation{simSpace=s,simW=w} x y = s ! (y*w+x)
+simSet sim@Simulation{simSpace=s,simW=w,simH=h} c x y = sim { simSpace = (s // [(y*w+x,c)]) }
+simGetChunkType sim x y = chunkType $ simGet sim x y
-veccSet v w c i = v // [(i,c)]
-simSet (Simulation s w h) c i = Simulation (veccSet s w c i) w h
+initSimSpace x y = Simulation
+ { simSpace = V.replicate (y*x) ChunkData { chunkType=Air }
+ , simW = x
+ , simH = y
+ }
-initSimSpace x y = Simulation (V.replicate (y*x) (ChunkData Empty)) x y
+testSim = let a = simSet (initSimSpace 10 10) (ChunkData Water) 5 5
+ in simSet a (ChunkData Wall) 5 6
-testSim = simSet (initSimSpace 10 10) (ChunkData Water) 5
+physStep sim@Simulation{simW=w,simH=h} = _physStep [(x, y) | x <- [0..w-1], y <- [0..h-1]] sim sim
+-- _physStep grid acc sim@Simulation{simSpace=s,simW=w,simH=h} | trace ("" ++ show h) False = undefined
+_physStep grid acc sim@Simulation{simSpace=s,simW=w,simH=h} =
+ if null grid then acc
+ else _physStep (tail grid) next sim
+ where x = fst $ head grid
+ y = snd $ head grid
+ valid = validDirects x y w h
+ next = case simGetChunkType sim x y of
+ Water -> updateWaterChunk x y valid acc
+ _ -> acc
+ -- spawn = simSet next (ChunkData Water) 5 0
-physStep sim@(Simulation _ w h) = _physStep 0 (initSimSpace w h) sim
-_physStep i acc sim@(Simulation s w h) =
- if i >= w*h then acc
- else _physStep (i+1) next sim
- where
- getChunkData (ChunkData c) = c
- next = case getChunkData $ simGet sim i of
- Water -> sim
- _ -> sim
+-- takes in list of valid chunks, as well as the sim to modify
+-- updateWaterChunk x y valid sim | trace ("x:" ++ show x ++ " y:" ++ show y ++ " " ++ show valid) False = undefined
+updateWaterChunk x y valid sim =
+ -- if the chunk below is free, fall straight down
+ if elem (0,1) valid && fromEnum (simGetChunkType sim x (y+1)) == fromEnum Air
+ then
+ let moved = simSet sim ChunkData { chunkType=Air } x y
+ in simSet moved ChunkData { chunkType=Water } x (y+1)
+ else if elem (-1,1) valid && fromEnum (simGetChunkType sim (x-1) (y+1)) == fromEnum Air
+ then
+ let moved = simSet sim ChunkData { chunkType=Air } x y
+ in simSet moved ChunkData { chunkType=Water } (x-1) (y+1)
+ else if elem (1,1) valid && fromEnum (simGetChunkType sim (x+1) (y+1)) == fromEnum Air
+ then
+ let moved = simSet sim ChunkData { chunkType=Air } x y
+ in simSet moved ChunkData { chunkType=Water } (x+1) (y+1)
+ else if elem (-1,0) valid && fromEnum (simGetChunkType sim (x-1) y) == fromEnum Air
+ then
+ let moved = simSet sim ChunkData { chunkType=Air } x y
+ in simSet moved ChunkData { chunkType=Water } (x-1) y
+ else if elem (1,0) valid && fromEnum (simGetChunkType sim (x+1) y) == fromEnum Air
+ then
+ let moved = simSet sim ChunkData { chunkType=Air } x y
+ in simSet moved ChunkData { chunkType=Water } (x+1) y
+ -- stay put
+ else sim
--- initGaussSeidel s =
--- where h = length s
--- w = length (s V.! 0)
+-- gets chunks around a given chunk that are inside grid
+-- validDirects x y w h | trace ("w:"++ show w ++ "h:" ++ show h) False = undefined
+validDirects x y w h = filter
+ (\q -> 0 <= (fst q)+x && (fst q)+x < w && 0 <= (snd q)+y && (snd q)+y < h)
+ [(a,b) | a <- [-1..1], b <- [-1..1], not (a==0 && b==0)]
+
+simToString :: Simulation -> [Char]
+simToString sim@Simulation{simW=w} =
+ let simStr = V.toList $ V.map chunkToChar $ simSpace sim
+ in insert w '\n' simStr
+
+-- from https://stackoverflow.com/questions/12659562/insert-specific-element-y-after-every-n-elements-in-a-list
+insert :: Int -> a -> [a] -> [a]
+insert n y xs = countdown n xs where
+ countdown 0 xs = y:countdown n xs
+ countdown _ [] = []
+ countdown m (x:xs) = x:countdown (m-1) xs
+
+-- stringToSim :: [String] -> Simulation
+stringToSim strings =
+ _stringToSim st grid (initSimSpace w h)
+ where stripped = strings
+ w = maximum $ [(length s) | s <- stripped]
+ h = length stripped
+ grid = [(a,b) | a <- [0..(length stripped)-1], b <- [0..(length $ stripped !! a)-1]]
+ st = concat stripped
+
+_stringToSim st grid acc =
+ if null grid || null st then acc
+ else _stringToSim (tail st) (tail grid) next
+ where y = fst $ head grid -- not exactly sure why y and x got switched here
+ x = snd $ head grid
+ next = simSet acc (charToChunk $ head st) x y
+
+-- maps each chunktype to an ascii character
+chunkToChar :: ChunkData -> Char
+chunkToChar c =
+ case chunkType c of
+ Water -> '~'
+ Air -> ' '
+ Wall -> '#'
+ _ -> '?'
+
+-- this is redundant, fix this somehow
+charToChunk :: Char -> ChunkData
+charToChunk c =
+ ChunkData { chunkType=ctype }
+ where ctype = if c=='~' then Water
+ else if c=='#' then Wall
+ else Air
--- gaussSeidel